Lakewood's public schools could be the first in New Jersey to require that backpacks and other containers used by students be transparent, under a policy formulated in response to a recent gun-related incident.

The policy, which will take effect in July, stems from a June 5 incident in which authorities said a .22 caliber handgun was seized outside an elementary school after a 9-year-old student had taken it onto a school bus and showed it to a 10-year-old.

In a follow-up interview on Friday, Inzelbach said he was not aware of any other district that had decided on or implemented a transparency requirement, which was devised in consultation with district staff and the police.

Inzelbach said the district had received inquiries from a dozen districts regarding its new policy, which applies to backpacks, book bags and any other carrying case.

"Anything students bring into school," Inzelbach said, adding that the requirement will take effect in July for summer school students, and in September for all others.

Frank Belluscio, a spokesman for the New Jersey School Boards Association, said Lakewood appeared to be the state's first district to impose such a policy.

"I am not aware of other districts in New Jersey that will be requiring clear backpacks," Belluscio said in an email Friday.

Four months after 17 people were killed in the Parkland school shooting in Florida, and four weeks after 10 students and teachers were shot to death in Santa Fe, Texas, the backpack industry appeared ready for requirements like Lakewood's.

A quick search on Amazon revealed a broad selection clear plastic and mesh backpacks and book bags ranging from the ProEquip at $5.98 to the Smorty for $37.97, plus dozens of others by JanSport, EastSport and other brands, many with colorful binding.

A spokesman for the New Jersey Department of Education said there was no movement on the state level to implement any kind of visibility requirement for bags in schools.

"That is an issue that is decided locally at the district level," the spokesman, Michael Yaple, said in an email.

"Some districts throughout the country implemented clear-backpack policies after Columbine," Yaple added, referring to the 1999 Colorado school shooting that left one teacher and 14 students dead, including the two shooters. The state "doesn't track backpack policies among districts," he said.

Video footage of the June 5 incident in Lakewood appeared to show the two boys on the bus loading bullets into the gun.

Another student who also had been on the bus told a school security guard, according to the district. And police said officers called to the scene found the weapon in the 10-year-old's backpack before it could be taken into the school.

Police said the two boys were arrested and charged with unlawful possession of a weapon, possession of a weapon for an unlawful purpose, and possession of a weapon on school grounds.

Inzelbach said the two students had not returned to school as of Friday, but rather were being schooled remotely.

"They've not been in school and police are still investigating the matter," Inzelbach said.